Someone please help me!!
Why is the idea of "sucking" up water with a straw misleading?

How does the rubber suction cup on a dart work?


Would such darts work in space?




Thanks for all your help!!

All 3 things are based on the difference between pressure inside and outside. You use your diaphragm to expand the volume of air between the top of the soda and your lungs. That lowers the pressure. The now higher pressure outside pushes the soda up the straw.

With the dart, it is the rubber in the suction cup expanding the air. Lower pressure inside, higher outside, the dart is pushed where it is stuck.

No pressure to lower, the suction cup doesn't work. In a pressurized space capsule, it would.